from numpy import  sqrt, power, log, round

def R(du, dv): return 1 / (sqrt(du * dv))

def M1(du, dv): return du + dv

def M2(du, dv): return du * dv

def ABC(du, dv): return sqrt((du + dv - 2) / (du * dv))

def SCI(du, dv): return 1 / (sqrt(du + dv))

def GA1(du, dv): return 2 * sqrt(du * dv) / (du + dv)

def AZI(du, dv): return  power((du * dv) / (du + dv - 2), 3) 

def HI(du, dv): return 2 / (du + dv)

def lnP1(du, dv): return log(du) / du + log(dv) / dv

def lnP1S(du, dv): return log(du + dv)

def lnP2(du, dv): return round(log(du) + log(dv))

def ALB(du, dv): return abs(du - dv)


        
